Water Heater Components: The Dip Tube

As you’ve certainly noticed before, your conventional water heater is quite large. And although these system may look like they contain a lot of complicated mechanisms that would be difficult to fix, many of the parts that are often responsible for water heater trouble can be somewhat simple to repair when the job is completed by a trained technician. One of these parts is the dip tube, a piece that is vital to water heater operation despite its simple design.

Storage tank water heaters, the most common type of water heater found in home, are still in such widespread use today despite the development of tankless water heaters that are much smaller. Much of the credit for the longevity of the storage tank goes to its simple but effective design. Water flows into the tank through the water supply pipe that feeds to the top of it. It moves into a long pipe that leads to the bottom of the tank known as the dip tube.

The cold water that first enters the tank must be pushed to the bottom of the tank for two reasons. First, this is where the burner is located, or it’s where one of two electric heating elements are positioned in an electric unit. Second, the heat rising principle establishes that the warm water will naturally rise over the denser cold water to the top of the tank. Hot water waits at the top of the tank and flows out through a smaller pipe at the top whenever you turn on a hot water tap.

So without a dip tube to force cold water to the bottom of the tank, water is not able to stay warm for very long. When you first turn on your hot water, it may be sufficient, but as your hot shower goes on, you’ll notice cooler water or patches of warm and cool. If the dip tube splits in half or cracks apart, cold water is able to stat at the top of the tank before it is heated. When this happens, a technician will usually replace the tube rather than attempting to seal the leak.